Brown Institute for Brain Science

Tail Suspension Test

Rationale of Test

This task is used to assess depressive-like behavior (or a form of learned helplessness). Animals that are considered more depressive tend to give up sooner and more completely when faced with a high degree of adversity.

Apparatus

A section (5mm) of rubber tubing is attached to the ceiling of an isolation chamber and attached to the tip of the tail of the mouse being testing. The isolation chamber is placed in front of a digital camera connected to a computer with a digitizer board and video tracking software.

Procedure

The tail suspension test is carried out in an isolation chamber to eliminate external cues from influencing the mouse’s behavior. Activity of the mouse is digitally recorded for 5 minutes and analyzed offline to measure immobility (a measure of depressive like behavior). Immobility is measured using the mobility function on automated tracking software. To validate automated scoring measures, a subset of videos are scored blind to condition by a highly trained observer. Mice are considered immobile when they dangle from the ceiling with no attempt to right themselves.

Interpretation

In this task, more depressive animals give up and stop struggling sooner and more completely, whereas less depressive animals tend to attempt to right themselves for greater period of time.

Relevant Controls

Care should be taken to insure no differences between groups in motor function, motor coordination, motor endurance, and balance.